This invention relates to and provides a tube scraper for cleaning the interior surface of heat exchanger tubes such as boiler tubes and condenser tubes.
In normal operation, hard deposits such as rust and scale containing calcium, and soft deposits including slime and loose dirt build up on the interior surface of heat exchanger tubes that diminishes thermal efficiency and restricts fluid flow through the tubes. To maintain thermal efficiency and design flow in operation of the heat exchanger, it is necessary to remove such deposits.
These deposits are removed by mechanical scraping using a projectile driven through the tube by pressurized media including air, water, steam, or other gas. The pressure media acts on a projectile seal or piston for propelling the projectile through a tube. The projectile is fitted with scrapers engaging the tube interior wall for removing deposits as the projectile transits the tube. Preferably, the projectile pushes removed deposits ahead through the tube so both projectile and deposits are ejected from the far end of the tube.
The chief objective of the present invention is to provide an improved scraper for removing hard deposits from the interior surface of heat exchanger tubes.